This allows max6650 devices to be referenced in dts as a cooling device.
The pwm value seems duplicated in cooling_dev_state but since pwm goes
through rounding logic into data->dac, it is modified and messes with
the thermal zone state algorithms. It's also better to serve a cache
value, thus avoiding periodic actual i2c traffic.
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@xxxxxxxxx>
---
Changes in v2:
Removed left-over debug printk.
Changes in v3:
Add missing dependency in Kconfig
drivers/hwmon/Kconfig | 1 +
drivers/hwmon/max6650.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 91 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d0f1dfe2bcbb..46d69fcdd48b 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -898,6 +898,7 @@ config SENSORS_MAX6642
config SENSORS_MAX6650
tristate "Maxim MAX6650 sensor chip"
depends on I2C
+ depends on THERMAL || THERMAL=n
help
If you say yes here you get support for the MAX6650 / MAX6651
sensor chips.
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
index 61135a2d0cff..f1cbbaaa1206 100644
--- a/drivers/hwmon/max6650.c
+++ b/drivers/hwmon/max6650.c
@@ -40,6 +40,7 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/of_device.h>
+#include <linux/thermal.h>
/*
* Insmod parameters
@@ -113,6 +114,7 @@ module_param(clock, int, 0444);
struct max6650_data {
struct i2c_client *client;
const struct attribute_group *groups[3];
+ struct thermal_cooling_device *cooling_dev;
struct mutex update_lock;
int nr_fans;
char valid; /* zero until following fields are valid */
@@ -125,6 +127,7 @@ struct max6650_data {
u8 count;
u8 dac;
u8 alarm;
+ unsigned long cooling_dev_state;
};
static const u8 tach_reg[] = {
@@ -694,6 +697,63 @@ static int max6650_init_client(struct max6650_data *data,
return 0;
}
+#if IS_ENABLED(CONFIG_THERMAL)
+/* thermal cooling device callbacks */
+static int max6650_get_max_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ *state = 255;
+
+ return 0;
+}
+
+static int max6650_get_cur_state(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct max6650_data *data = cdev->devdata;
+
+ *state = data->cooling_dev_state;
+
+ return 0;
+}
+
+static int
+max6650_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
+{
+ struct max6650_data *data = cdev->devdata;
+ struct i2c_client *client = data->client;
+ int err;
+
+ state = clamp_val(state, 0, 255);
+
+ mutex_lock(&data->update_lock);
+
+ if (data->config & MAX6650_CFG_V12)
+ data->dac = 180 - (180 * state)/255;
+ else
+ data->dac = 76 - (76 * state)/255;
+
+ err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
+
+ if (!err) {
+ max6650_set_operating_mode(data, state ?
+ MAX6650_CFG_MODE_OPEN_LOOP :
+ MAX6650_CFG_MODE_OFF);
+ data->cooling_dev_state = state;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return err < 0 ? err : 0;
+}
+
+static const struct thermal_cooling_device_ops max6650_cooling_ops = {
+ .get_max_state = max6650_get_max_state,
+ .get_cur_state = max6650_get_cur_state,
+ .set_cur_state = max6650_set_cur_state,
+};
+#endif
+
static int max6650_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -709,6 +769,7 @@ static int max6650_probe(struct i2c_client *client,
return -ENOMEM;
data->client = client;
+ i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
data->nr_fans = of_id ? (int)(uintptr_t)of_id->data : id->driver_data;
@@ -727,7 +788,34 @@ static int max6650_probe(struct i2c_client *client,
hwmon_dev = devm_hwmon_device_register_with_groups(dev,
client->name, data,
data->groups);
- return PTR_ERR_OR_ZERO(hwmon_dev);
+ err = PTR_ERR_OR_ZERO(hwmon_dev);
+ if (err)
+ return err;
+
+#if IS_ENABLED(CONFIG_THERMAL)
+ data->cooling_dev =
+ thermal_of_cooling_device_register(client->dev.of_node,
+ id->name, data,
+ &max6650_cooling_ops);
+ if (IS_ERR(data->cooling_dev)) {
+ err = PTR_ERR(data->cooling_dev);
+ dev_err(&client->dev,
+ "Failed to register as cooling device (%d)\n", err);
+ return err;
+ }
+
+ thermal_cdev_update(data->cooling_dev);
+#endif
+ return 0;
+}
+
+static int max6650_remove(struct i2c_client *client)
+{
+ struct max6650_data *data = i2c_get_clientdata(client);
+
+ thermal_cooling_device_unregister(data->cooling_dev);
+
+ return 0;
}
static const struct i2c_device_id max6650_id[] = {
@@ -743,6 +831,7 @@ static struct i2c_driver max6650_driver = {
.of_match_table = of_match_ptr(max6650_dt_match),
},
.probe = max6650_probe,
+ .remove = max6650_remove,
.id_table = max6650_id,
};
--
2.11.0
